Horizontal and vertical transmission of dengue virus type 2 in highly and lowly susceptible strains of Aedes aegypti mosquitoes.

Isofemale lines of Aedes aegypti mosquitoes highly and lowly susceptible to dengue type 2 (DEN-2) virus (DEN(h) and DEN(l), respectively) were established by oral feeding and individual rearing. The susceptibility at F13 generation was found to be 61% and 25% for the DEN(h) and DEN(l) line, respectively. The virus-infected mosquito females were allowed to probe on bovine albumin phosphate saline pH 7.2 (BAPS) through membrane feeders. The presence of virus in the probed BAPS was determined either by ELISA or by intrathoracic (i.t.) inoculation of mosquitoes or by both methods. The rate of oral transmission of virus was found to be 2 times higher in the DEN(h) isofemale line than in the DEN(l) one. Similarly, vertical transmission rate of the virus was found to be 7 times higher in the DEN(h) line. When batches of eggs obtained from infected female mosquitoes were allowed to hatch after two months the vertical transmission rate of the virus was very high. It is possible that, at room temperature, the virus gets an opportunity to multiply and increase its copy number in the quiescent embryos. The progeny obtained from the infected mosquitoes was found to be capable of transmitting the virus horizontally when allowed to probe on BAPS through the membrane feeder. This is the first report demonstrating horizontal transmission of DEN-2 virus by mosquitoes infected through vertical transmission. The higher vertical transmission rate of the virus in the progeny obtained from the eggs dessicated for a longer time and the horizontal transmission of the virus from the progeny is of very high epidemiological significance.     

Changing clinico-laboratory profile of encephalitis patients in the eastern Uttar Pradesh region of India

A cross-sectional study was done on 100 consecutive paediatric patients presenting with acute encephalitis syndrome. The clinico-laboratory features of all patients were recorded in a prestructured performa. Cerebrospinal fluid and serum samples were tested for: Japanese encephalitis (JE) virus; Chandipura virus; coxsackie virus; dengue virus; enterovirus 76; and West Nile virus. Twenty-two (22.0%) patients were confirmed JE cases and 17% had parasitic or bacteriological aetiology. The remaining 61 cases (61.0%) in which no viral aetiological agent was found were grouped as non-JE cases. Peripheral vascular failure, splenomegaly and hypotonia were distinguishing clinical features found in the non-JE patients. A high mortality of 26.5% was seen in patients with confirmed or presumptive viral encephalitis (22/83). A fatal outcome was independently associated with peripheral vascular failure and pallor at the time of admission. Early recognition of these signs may help clinicians to manage these cases.     

Kinetics of peripheral blood mononuclear cell mobilization with chemotherapy and/or granulocyte-colony-stimulating factor: implications for yield of hematopoietic progenitor cell collections

BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.     

Management of Velopharyngeal Disorders. A Case Series

Patients with acquired defects or congenital malformations of the palate exhibit disturbances in speech, including hypernasality, nasal emission, and decreased intelligibility of speech. Maxillofacial prosthetic treatment can reestablish the palatopharyngeal integrity to provide the potential for acceptable speech. This article describes a case series of patients with palatopharyngeal disorders and their treatment approaches.     

Rare detection of hepatitis B and hepatitis C virus genomes by polymerase chain reaction in seronegative donors with elevated alanine aminotransferase

BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous.     

中国人胚胎肝组织来源纤溶酶原kringle5基因的克隆与序列分析

目的：分离、克隆和测定中国人纤溶酶原Kringle5功能区基因，为进一步研究其功能奠定基础。方法：实验于2002—06／2003-05在广州医学院金域医学检验中心完成。①实验材料：国人胚肝组织取自广州医学院第一附属医院的流产胚胎（取得家属同意，并经广州医学院第一附属医院伦理委员会批准）。pET21a（＋）载体购自Novagen公司，大肠杆菌BL21（DE3）为医学检验中心保存。引物均由上海生工合成。②实验方法：从国人胚肝组织中提取mRNA，用反转录-聚合酶链反应方法将人纤溶酶原Kringle5的cDNA扩增出来，克隆到pET21a（＋）载体中测序。（D实验评估：采用紫外分光光度仪和琼脂糖凝胶电泳分析胚肝组织总RNA的抽提结果；经琼脂糖凝胶电泳鉴定Kringle5的反转录-聚合酶链反应扩增结果；pET-Kringle5重组质粒的酶切鉴定；序列测定。结果：①胚肝组织提取总RNA结果：提取的总RNA经紫外分光光度仪测得A260nm/A80nm〉1．8，A60nm，A270nm〉1.2，表明无蛋白残留；电泳结果显示提取的总RNA有明显的28S、18S两条带，说明RNA基本完整。②Kringle5的反转录-聚合酶链反应扩增结果：人Kringle5 cDNA片段长为240bp，加上引物设计的2个酶切位点，总长度为258bp，聚合酶链反应产物长度与该长度一致，符合预期结果。③）pET-Kringle5重组质粒的构建和酶切鉴定结果：用引物所带的限制性内切酶BamH Ⅰ、NdeⅠ双酶切，结果有250bp左右条带出现。④序列测定结果：证实国人纤溶酶原Kringle5功能区基因被成功克隆，序列分析证实为该基因，未发现有基因突变或多态性现象，但第153位核苷酸与文献比较存在碱基替代现象，其组成的密码子由于遗传的简并性，所编码的氨基酸相同，并未造成氨基酸组成的改变。结论：中国人纤溶酶原Kringle5功能区cDNA基因编码序列与国外文献报道的相应序列可能存在碱基替代现象。     

Systemic inflammation after inspiratory loading in chronic obstructive pulmonary disease

Objective

Patients with chronic obstructive pulmonary disease (COPD) present systemic inflammation. Strenuous resistive breathing induces systemic inflammation in healthy subjects. We hypothesized that the increased respiratory load that characterizes COPD can contribute to systemic inflammation in these patients.

Patients and methods

To test this hypothesis, we compared leukocyte numbers and levels of circulating cytokines (tumor necrosis factor alpha [TNFα], interleukin-1β [IL-1β], IL-6, IL-8, and IL-10), before and 1 hour after maximal incremental inspiratory loading in 13 patients with stable COPD (forced expiratory volume in one second [FEV₁] 29 ± 2.5% ref) and in 8 healthy sedentary subjects (FEV₁ 98 ± 5% ref).

Results

We found that: (1) at baseline, patients with COPD showed higher leukocyte counts and IL-8 levels than controls (p < 0.01); and, (2) one hour after maximal inspiratory loading these values were unchanged, except for IL-10, which increased in controls (p < 0.05) but not in patients with COPD.

Conclusions

This study confirms the presence of systemic inflammation in COPD, shows that maximal inspiratory loading does not increase the levels of pro-inflammatory cytokines (IL-1β, IL-8) in COPD patients or controls, but suggests that the former may be unable to mount an appropriate systemic anti-inflammatory response to exercise.     

Trichomonas vaginalis in HIV/AIDS subjects in Nigeria

ObjectiveTo determine the prevalence of Trichomonas vaginalis (T. vaginalis) in HIV/AIDS patients attending two different hospitals in southeast Nigeria.MethodsWe collected 970 urine samples from HIV/AIDS patients attending two different hospitals in southeast Nigeria. Samples were processed by microscopy and cultural methods.ResultsOut of the 970 screened, 355 (36.60%) were positive for T. vaginalis. Subjects with the least CD4⁺ count in the range of 40-140 cells/mL had the highest number of positive samples (180, 50.70%), while those in the range of 480-580 cells/mL had the least value (2, 0.56%). Those in the rural areas had a higher number of positive samples (155, 38.75%) than their urban counterparts (200, 35.09%) with respect to the total number examined in each group but this was not statistically significant (P>0.05). Out of the 355 positive cases, the university undergraduate students’ group had the highest percentage incidence of 53.00% followed by the low-income group with 47.08%.ConclusionsIt can be concluded that the occurrence of T. vaginalis increases with decrease in the CD4⁺ counts in HIV/AIDS patients in Nigeria. Since T. vaginalis may be an important cofactor in promoting the spread of HIV and, in some circumstances, may have a major impact on the epidemic dynamics of HIV, there is a need to take measures to check the spread of this parasitic infection.     

中老年人糖化血红蛋白水平与颈动脉内膜-中层厚度的相关性研究:广州生物库心血管疾病亚队列

目的 探讨相对健康的中老年人血中糖化血红蛋白(HbAlc)含量对颈动脉硬化的影响.方法 从广州生物库队列中单纯随机抽样收集1863名年龄≥50岁的广州市居民的个人资料,问卷调查其病史、体格检查及测定血清空腹血糖、血脂、HbA1c的含量并应用彩色多普勒超声测量颈总动脉内膜-中层厚度(intima media thickness,IMT).在调整相关混染因素后,应用协方差分析进行连续变量分析.结果 (1)在调整年龄、性别和空腹血糖等因素后,平均颈总动脉IMT随HbA1c含量升高呈明显增加趋势(P=0.005).线性回归模型显示,在调整年龄、性别、吸烟状态、腰围、收缩压和舒张压、甘油三酯、高密度脂蛋白胆固醇、低密度脂蛋白胆固醇和空腹血糖等潜在危险因素后,结果仍然显示HbA1c水平与平均颈总动脉IMT有明显的线性相关(回归系数为0.014,P=0.03);(2)经过调整多种潜在混杂因素后,与HbA1c理想组(HbA1c<6.5%)比较,良好组(HbA1c为6.5%～7.5%)和差组(HbA1c>7.5%)发生颈动脉硬化的比值比(95%置信区间)分别为1.62(1.10,2.38)和1.76(0.86,3.63),趋势检验(P=0.01).结论 相对健康的中老年人HbA1c含量升高是颈动脉硬化的独立危险因素之一,提示降低HbA1c水平对阻止或延缓颈动脉硬化的发生与发展有重要意义.